Artificial tooth construction



Sept. 15, 1936.

B. L. BROOKS ARTIFICIAL TOOTH CONSTRUCTION Filed Oct. 21, 1933 2 Sheets-Sheet l R O T N E V m Sept. 15, 1936. BRQQKS 2 ,054,781

- ARTIFICIAL TOOTH CONSTRUCTION Filed Oct. 21, 1953 2 Sheets-Sheet 2 INVENTOR.

Patented Sept. 15, 1936 ARTIFICIAL TOOTH CONSTRUCTION Benjamin L. Brooks, Lynchburg, Va., assignor of one-half to ton, D. 0.

Robert J. Rothstein, Washing- Application October 21, 1933, Serial No. 694,673

3 Claims.

This invention relates to artificial tooth construction.

Primarily; the invention concerns itself with the occlusal or masticating surfaces of artificial 'teeth used as substitutes for natural teeth in the many different relations inwhich these members are associated, and particularly in dentures, or plate, crown and bridge-work used for that purpose. g

It is a well-known fact that dentists, in replacing natural teeth, have utilized artificial constructions the unitary teeth of which were designed as a close imitation; of the natural teeth. This attempt to imitate did not end with the facial and lingual surfaces of the teeth, where only appearance was involved. It even 'extended to the occlusal or masticating surfaces of such substitutes. Especially was this true with the units substituted for the bicuspids and molars, wherein not at all satisfactory results were attained. Patients, given dentures having units of this character, either found themselves unable to accustom themselves to such new apparatus, or found themselves subjected to many trials before that end could be attained. Somehow, the plate,

ing off the extended material defining the cusps,

at least caused an unnecessary and undesirable tipping and sliding movement of the denture base along. thepallet or ridge. of the jaws.

With continued action of this character, irritation, inflammation and soreness resulted. The increased irritation of the tissues forming the pallet andthe ridge, culminated in serious interference not alone with the comfort of the wearer of the particular denture, but materially with the substantially eliminated.

stability and functioning of that denture.

It is an object of the invention to provide an artificial tooth construction which, when arranged in the mouth as one of, a set of a plurality of .such members, while not reducing, in any'substantial degree, the positive masticating action desirably performed by cusps of the ordinary character, functions positively to eliminate possibility of interlocking the cusps. Although a .tooth element in accordance with the invention 7 is provided with cusps, that is, recessed indentations in the occlusal or masticating faces of the teeth, providing extending blades to cut the food and assist in grinding it, still these cusps are defined in such manner that opposed members may 5 not interlockingly engage each other, no matter what the movements of the jaws with relation to each other may be. Thus there are eliminated the annoyance and, sometimes, disastrous effects of artificial dentures.

In present-day dentures, it sometimes occurs that, as the jaws move in the mastication of food, the anterior teeth become positioned in overlapping relationship. It is not an uncommon incident that the anteriors become so overlapped with the lingual surface of one set of anteriors over the facial surface of the other set. Then results may follow which are far from pleasant, and even may be disastrous.

It is an object of the invention to provide a tooth element construction, for use in dentures of the character indicated, which, when positioned within the mouth, will result in a positioning of the elements so that any such relationship of anteriors would practically be impossible.

Artificial teeth of this character, and especially those to substitute for the'bicuspids and molars, are formed in a manner such that the occlusal surface of each unit slopes away from a medial section and toward the adjacent faces of adjacent teeth. Where two adjacent teeth are constructed in this manner, a valley is formed by the asso ciated and immediately adjacent sloping surfaces. If the opposed teeth be formed in substantially the same manner, the cusp ridge of one element may be seated in such a valley. In such a relation, the teeth will be locked against surface movement, forwardly and rearwardly, or, at least, such movement may occur only if the jaws bef moved slightly apart, when the occlusal surface of the opposed teeth may slide over each other. In a construction requiring such movement of the occlusal surfaces, the possibility that the opposed anterior teeth may'become engaged is Where tooth members are formed as here de-'-' scribed, it may occur that distinct spacing is permitted between the teeth, when operating to masticate. 'It-is an object of the invention to form occlusal surfaces of teeth with cusps formed and scientifically correctly disposed so that efficient mastication of food will result in a tooth relationship as just described.

Occlusal surfaces, in one construction, are

given a contouring approaching closely that of segments of a spherical surface, at least at the middle section of the occlusal surface of an individual tooth element. In instances shown, occlusal surfaces of opposed teeth have portions of their surfaces formed spherical, the opposed surfaces both being concave. A proper relationship of the teeth elements, when brought together, is thus assured. For certain purposes of the invention, one tooth surface may have a convexed formation; in opposed relation thereto would be a concaved member. When in abutment, these members would seat positively upon one another and in interlocking engagement with each other.

In the past, to define cusps for teeth, no. particular plan has been followed. Openings, ex-

tending inwardly from the top face of the tooth,

were formed, defining edges for engagement.

against food to be masticated, these edges providing an effective means for gripping food while it was ground. The functions, of such cusps. were not particularly evaluated so. that breaking of the edges of such members was not an uncommon occurrence.

It is an object of the invention to provide an occlusal surface for a tooth member including a plurality of depressed surfaces extending in amannerto define cusps. Surfaces and cusps extend substantially continuously, in one case, from facial to lingual faces of the-teeth; Interdigi-tating channels maybe constructed tocooperate with cusps of this character as, forinstance, by being formed through the walls defining the cusps. Food, or substances becoming deposited within the cusps, may, by the ordinary operations of mastication be caused to move around within the cusps, and, finally with continued mastication, even be separated from the teeth.

With shrinkage of pallet or ridge of the jaw,

a'denturebase follows along, and the tissues attempt to adjust themselves to the new position. This change of the-denture position, in itself, may causethe exertion-of great pressure on the lingual surfaces of upper anterior tooth elements, es-

;pecially where anterior tooth elements do not come together in a tip-to-tip bite when closed toof the occlusal surfaces at the molar tooth elements cooperate for producing the result of constant contact throughout the biting operation. Such'contact, and the resultant fulcrum action produced, function to press the. dentures into position against the pallet or ridge of the jaws.

The base, so forced into. position, is retained against becoming dislodged, or slipping away at the rearmost. portion of the mouth.

I In connection with a tooth construction of the I type indicated, none of the desired appearance of natural teeth need be lost, facial and lingual surfaces of the tooth element lending themselves.

readily to a proper contouring for attaining such fappearance.

Other objects of this invention will hereinafter be set forth, or will be apparent from the description and the drawings, in which are illustrated embodiments of dentures and elements thereof capable of carrying out the invention.

The invention, however, is not intended to be restricted to any particular construction or arrangement of parts, or to any particular application of such construction, or to any specific manner of use, or to any of various details thereof herein shown and described, as the same may be modified in various particulars, or be applied in many varied relations, without departing from the spirit and scope of the claimed invention, the practical embodiments herein illustrated and described showing some of various forms and modifications in which the invention may be practised.

On the drawings, in which the same reference characters refer to the same parts throughout, and in which are disclosed some of such embodiments:

Fig. 1 is an elevational view of a portion of a pair of opposed dentures, positioned in abutting relationship, the dentures including tooth elements embodying features: of the invention;

Fig. 2 is a plan view of a portion of one of such dentures;

Fig. 3-is atransverse, vertical cross-sectional View, on the line 33 of Fig. 2;

Fig. 4 is a transverse, vertical cross-sectional View, on the line 4-4 of Fig. 3;

Fig. 5 is a transverse, vertical sectional view, on the line 55 of Fig. 2, of a tooth-element substantially without spherical contouring of the occlusal face;

' Fig. 6 is a view, in elevational perspective, of an artificial tooth-element such as shown in- 5, shown removed from its seat and having features of the invention;

Fig. 7" is a view, similar'to Fig. 2, illustrating the construction of a tooth element embodying; features of the invention in modified form;

Fig. 8 is a view, similar to Fig. 7', in which the invention is embodied in still another modified form; V

Fig. 9 is' a vertical cross-sectional view, transversely through two opposed dentures having elements embodying the-invention, and substantially as such a section would appear from line 99 of Fig. 1;

Fig. 10 is a view, similar to Fig. 9-, except that, in this instance, the occlusal surfacesof opposed tooth elements have been modified to a different relationship;

Fig. 11 is a cross-sectional view, similar to, Fig; 5, except that theocclusal face has spherical contouring; and

Fig. 12- is a view in-elevational perspective, similar to Fig. 6, illustrating the modifiedform of tooth element shown in Fig. 11.

On the drawings, theinventionhas-been shown applied in connection with a denture ID of any The elements of invention constructed along: the lines ofthe same principles of invention,

Facial and lingual faces Hand 22, respectively, of each element [4 may be contoured substantially as is a natural tooth. Thereby, from outside the mouth, the elements will present a uniformly natural appearance, even to the extent of giving no hint of their artificiality. In the construction of occlusalsurfaces 24 are introduced features makingmore eflicient the mastication thereby of food, and the anchoring in position of the dentures after they have been located in the mouth. Such occlusal surface may include a plurality of recesses 26 formed in the surface, defined by walls 28. The top surfaces 30. of these walls unite in defining the surface, here termed the occlusal surface of the tooth.

Therefore, the occlusal surface may be considered as a continuous top surface for the tooth, but into that surface have been cut recesses 26, leaving walls 28. The occlusal surface has a distinctly appearing slope from the edges adjacent proximate tooth elements toward a line in the surface centrally across the element, as, for instance, the imaginary line 32. Faces 30 cooperate in defining this formation so that, from the side, the tooth has the appearance of a wide V'.

Now considering the formation of the occlusal surface buccally and lingually, there is found to be a contouring along the lines shown in Fig. 3. Therefore, in addition to the inclination from the medial line toward the side edges, there is produced a concavity 34, the combination of an inclined plane with a spherical or similarconcavity forming the occlusal surface of the tooth element. The spherical contouring thus produced, may, for certain purposes, be substantially that of a fourinch sphere.

When two opposed dentures l and 36, are brought together, as in Fig. 1, molars I6 of lower jaw 38 will be in a relationship to molars 40 of upper jaw 42 substantially as shown in that figure. A ridge 44 of a tooth element will be received within an interdigitating channel 46 formed as a valley by the cooperation of two inclined surfaces of two adjacent tooth elements.

Any lateral movement of the teeth may be effected without annoyance as the ridges will slide within their respective channels. Mastication may, therefore, be efliciently carried on by lateral movement. If the jaws move forwardly and backwardly with relation to each other, a rise and fall of the. dentures with relation to each other occurs as the tooth elements ride up the incline provided on each of the molars and premolars.

But an additional function is found when the incisors 48, in associated anterior teeth 50, are functioning. The molars will be in contact with each other by reason of their peculiar interlocking formation. With this force of contact, food, seized between anterior tooth elements, normally will have a tendency to tip those tooth elements outwardly, and even to drive the plates themselves out of their engaged relationship upon pallet or ridge. However, in the construction herein, such tipping and separation of the denture from its properly engaged condition is resisted, in this case, by the related functioning of molars formed as herein described.

Recesses 26, which function at least in part as do the cusps of natural teeth, are defined by walls 28 whose general direction is from the facial to the lingual faces of the elements. As shown in Fig. 2, element 52, a simple form, has walls 54 slightly curved and leaving recesses 26 as cusps for the proper operation upon food.

In -Fig.. 6 is disclosed substantially the construction of element 56 wherein there is nocentrally rounded portion, while in Fig. 12, substantially the same element is shown, but with a rounded concavity centrally disposed in the occlusal surfaces.

Element 56 illustrates a modified construction especially desirable at the molar position where the occlusal surface is so much larger than in the premolar position of element 52. In this instance, an additional wall 58 is provided, extending inwardly from, but not necessarily united with, the other walls. In this case, this wall is shown connected at one end to the other wall. In this manner, cusps 66 and 62 are permitted interconnection through passage 64, while another passage 66 may function to drain both of these cusps, as well as to provide a self-cleaning, additional edge for the occlusal surface.

In Fig. 7 is shown another modified form. In this case, element 68 has its occlusal surface defined by a plurality of walls through a number of which passages 12 may be formed to assure intercommunication of these various cusps. At the same time, outer wall 14, bounding the occlusal surface, may be cut away at a number of points in order to position a plurality of passages 16 from the several cusps. In the case of element 18, the multiple status of the cusps and the enlarged condition of the molar faces results in the introduction of an additional wall 88.

In Fig. 8 is shown another modified form 82, substantially similar to that in Fig. '7 as far as the interconnection of the cusps is concerned. However, openings 84, in wall 86 bounding the occlusal surface on each element 82, are formed only at the lingual face. In this manner, drainage and removal of material, caught in the cusp,

is made efficient only in the direction of the lingual faces. By the same construction, the wall is not cut at the very tip end of the cusp, but at an intermediate point closely adjacent the point where wall 86 comes into contact with a like wall of an adjacent element. In this manner, access to the cusp is provided at an intermediate point in its extent, reducing the. distance for movement of material to be removed from within the cusp.

In .tooth elements, stationed as shown in Fig. 1, with spherically or concavely contoured surfaces opposed by a ridge 44, if a section be cut vertically of the opposed tooth elements, a result such as in Fig. 9 will appear. Between the opposed dentures of which Fig. 9 is a section, there will appear a separation of the spherically contoured surfaces, leaving a concavity 84 within which food may be caught. Efficient operation of the tooth elements occurs since the teeth normally, in mastication, do not take part only in a particular single movement, but there occurs movement simultaneously forwardly, laterally and vertically. The lateral movement will bring high points 86 of the elements into physical contact with food caught in the concavity, with resultant tearing or grinding, as the case may be. In any case, separation of the food from its engaged or entrapped condition between the occlusal surfaces necessarily occurs.

In the form shown in Fig. 10, the opposed tooth elements 88 and 96 of a pair of dentures are intended to have complementary surfaces 92 and 94, rather than similarly shaped surfaces. In this construction, if one tooth has a concaved surface 92, the other will have a complementary convex surface 94. When at rest, the surfaces,

brought into the relationship shown in Fig. 10, will seat one immediately within the other, and so be retained against movement.

In Fig. 11 is illustrated a tooth after havin been out along a line, showing the formation of the ridge and the slope away from the ridge in two directions, that is, toward the labial and lingual surfaces, as well as in the direction of an adjacent tooth element. As appears in Fig. 4, a cut transversely of a tooth element as shown in Fig. 3 will produce a formation defining a planar surface, except for the indentations of recess 26 defining the cusps.

Many other changes could be effected in the particular articles of manufacture here discussed, and in the manner of use set forth, and in specific details thereof, without substantially departing from the invention intended to be defined in the claims, the specific description herein being of embodiments operative for, and illustrating applications of, the spirit of the invention.

What is claimed as new and useful is:-

1. In artificial tooth construction for artificial dentures to replace removed natural human teeth, a member having contouring at lingual and facial side faces substantially simulating the contouring of the natural tooth for which it is intended to be a substitute, the member having an occlusal surface the extreme upper portions of which are shaped from facial to lingual faces into a surface approximately an elemental portion of the contouring of the surface of a sphere and to slope gradually mesially and distally to a ridge extending from facial to lingual faces of the member, said portions comprising a plurality of surfaces in relief extending from the facial to the lingual surfaces and bounding a plurality of recessed areas in the occlusal surface, at least one of the recesses having an opening at a lateral face of the member, the contoured portions of a pair of members, when disposed in a denture in sideby-side relationship, cooperating to define a depression between the pair of members so that, when members are made parts of opposed dentures in the mouth of a patient, the ridge of one member will be received in the depression and the spherically contoured surfaces will be disposed in opposed relationship.

2. In artificial tooth construction for artificial dentures to replace removed natural human teeth, a member having contouring at lingual and facial side faces substantially simulating the contouring of the natural tooth for which it is intended to be a substitute, the member having an occlusal surface the extreme upper portions of which are shaped from facial to lingual faces into a surface approximately an elemental portion of the contouring of the surface of a sphere and to slope gradually mesially and distally to a ridge extending from facial to lingual faces of the member, said portions comprising a plurality of surfaces in relief extending from the facial to the lingual surfaces and bounding a plurality of recessed areas in the occlusal surface, at least one of the recesses having an opening at a lateral face of the member, the contoured portions of a pair of members, when disposed in a denture in side-by-side relationship, cooperating to define a depression between the pair of members so that, when members are made parts of opposed dentures in the mouth of a pa-' tient, the ridge of one member will be received in the depression and the spherically contoured surfaces will be disposed in opposed relationship but intermediately between facial and lingualsurfaces the occlusal surfaces will be out of contacting relationship.

3. In artificial tooth construction for artificial dentures to replace removed natural human teeth, a member having contouring at lingual and facial side faces substantially simulating the contouring of the natural tooth for which it is intended to be a substitute, the member having a. plurality of blades extending upwardly therefrom, the tops of the blades being located in a surface contoured to slope gradually mesially and distally to a ridge extending from facial to lingual faces of the member, the sloping surface having characteristics of the surface of a spherical sector, the blades following the curvature of the side faces of the member from lingual to facial sides of the member.

BENJAMIN L. BROOKS. 

